I have a stock se suspension, but after I installed my stillen fstb, I hear occasional groaning or some noise I dunno how to describe when going over small speed bumps slowly.

 

I'm having the same issue with my stock strut (front right) without the FSTB. Dealer is replacing them. i would suggest you take the FSTB off and see if it's still there, if it is, then the struts might need to be replaced.

As of right now, the front struts are so back ordered because of this issue that its going to take well over 3 weeks for them to get the new parts.

 

there is a rubber padding on the bottom of the front springs which wraps around the springs and can be seen if you peep. if this rubber is missing or drop off, your springs can squeak and make noise, it might not be the shocks and also check that the fstb is not tightened too much on one side. it has to be balanced adjustments. i know, because this happened to me b4.